New Species and Names in Ecuadorian Grasses (Poaceae)

Abstract

Six species of grasses (Poaceae: Pooideae) from Ecuador are described as new: Calamagrostis carchiensis, C. ecuadoriensis, C. fulgida, C. Ilanganatensis, C. teretifolia, and Poa paramoensis; one new name is proposed: Calamagrostis fibrovaginata; and three new combinations are made: Calamagrostis hirta, Festuca vaginalis, and Nassella ibarrensis. RESUMEN. Seis especies de gramineas (Poaceae: Pooideae) del Ecuador se describen como nuevas: Calamagrostis carchiensis, C. ecuadoriensis, C. fulgida, C. Ilanganatensis, C. teretifolia y Poa paramoensis; se propone un nombre nuevo: Calamagrostis fibrovaginata; y se hacen tres nuevas combinaciones: Calamagrostis hirta, Festuca vaginalis y Nassella ibarrensis. As a result of the listing of grass species for the forthcoming Catalogue of Vascular Plants of Ecuador, six new species are described, a new name is proposed to replace an illegal homonym, and three new combinations are made, all in the subfamily Pooideae. Five of the new species belong to the genus Calamagrostis. Calamagrostis is an important genus in all piramos and other high-altitude vegetation types in Andean regions. In Ecuador 21 species were known until now. Numerous older studies of the genus, with Deyeuxia included, were summarized by Hitchcock (1927). Since then, a couple of new species were described for Ecuador by Swallen (1948), and a section of the genus, Stylagrostis, was studied and one new species for Ecuador was described by Escalona (1988a, 1988b). The Peruvian species were revised by Tovar (1960, 1993) and the Bolivian species recently by Villavicencio (1995). In the lower mountain regions of Ecuador, from ca. 1500 to ca. 2500 m, only the three broadand soft-leaved species, Calamagrostis rupestris Trinius, C. planifolia (Kunth) Trinius, and C. viridiflavescens (Poiret) Steudel, occur, and they are mainly found in disturbed ground. Calamagrostis viridiflavescens has only been observed in weedy or other clearly anthropogenic vegetation types and may have been introduced. Only relatively few species of Calamagrostis occur in the regularly burned grass pairamos at approximately 3300-4100(-4300) m that are considered rather recent secondary vegetation types by Laegaard (1992). Calamagrostis recta (Kunth) Trinius ex Steudel is common and often dominant in all of these piramos. Calamagrostis effusa (Kunth) Steudel is common and often codominant in the northernmost regions of Ecuador, the provinces of Carchi and Imbabura, while C. macrophylla (Pilger) Pilger occurs in the same way in southern Ecuador in the Loja province. Besides these C. rigida (Kunth) Trinius ex Steudel, C. intermedia (Presl) Steudel, and C. bogotensis (Pilger) Pilger are found more scattered in grass piramo vegetation but also seem to be tolerant to regular burning. In the same altitudinal region a number of other species occur, but these are mainly confined to moist ground and swamps where they are protected against fires. These include C. fibrovaginata Laegaard, C. jamesonii Steudel, C. ligulata (Kunth) Hitchcock, and C. rigescens (Presl) Schribner. The remaining species, including most of those described in the present paper, mainly occur in superpiramos from about 4100 m upward (Laegaard, 1992) where fires rarely or never occur. Several species have been found close to the limit for plant life in Ecuador at about 5000 m. In these superpiramos they may occur in dry biotopes, for example, C. mollis Pilger, or in moist sites, for example, C. guamanensis Escalona and C. podophora Pilger. However, several species are only known from a few herbarium specimens, and their ecology remains to be studied. Calamagrostis carchiensis Laegaard, sp. nov. TYPE: Ecuador. Prov. Sucumbfos: P6ramo de Mirador above Cocha Seca, lower pramo zone, burned, 77?39'W, 0?34'N, 3700-3900 m, 23 May 1985, Legaard 54413 (holotype, AAU; isotypes, K, MO, QCA, QCNE, US). Figure 1A. Planta rhizomatosa vel laxe caespitosa. Panicula longa, angusta, dense florida; spiculae 3.5-4 mm; dorsum totum lemmatis scabridiusculum; arista tenuissima ca. 0.7 mm; callus sine pilis; elongatio rachillae 0.7-1.2 mm, sparsissime breve pilosa. Single stems from rhizomes or small, loose tussocks, 50-85 cm high, leaves mainly cauline. NovoN 8: 23-30. 1998. This content downloaded from 207.46.13.118 on Sun, 11 Sep 2016 06:01:01 UTC All use subject to http://about.jstor.org/terms